Once again, no joy. Here's the whole sorry pantload:
 
12:43:09,353 WARN  [org.jboss.modules] (MSC service thread 1-3) Failed to define class org.jboss.as.jpa.hibernate3.infinispan.SharedInfinispanRegionFactory in Module "deployment.waimap.ear:main" from Service Module Loader: java.lang.LinkageError: Failed to link org/jboss/as/jpa/hibernate3/infinispan/SharedInfinispanRegionFactory (Module "deployment.waimap.ear:main" from Service Module Loader)
        at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:396) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ModuleClassLoader.loadClassLocal(ModuleClassLoader.java:243) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ModuleClassLoader$1.loadClassLocal(ModuleClassLoader.java:73) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.Module.loadModuleClass(Module.java:517) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:182) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:468) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:456) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:423) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:398) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:120) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.as.jpa.hibernate3.HibernatePersistenceProviderAdaptor.<clinit>(HibernatePersistenceProviderAdaptor.java:49)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) [classes.jar:1.6.0_30]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) [classes.jar:1.6.0_30]
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) [classes.jar:1.6.0_30]
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513) [classes.jar:1.6.0_30]
        at java.lang.Class.newInstance0(Class.java:355) [classes.jar:1.6.0_30]
        at java.lang.Class.newInstance(Class.java:308) [classes.jar:1.6.0_30]
        at org.jboss.as.jpa.processor.PersistenceProviderProcessor.deploy(PersistenceProviderProcessor.java:101)
        at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:113) [jboss-as-server-7.1.1.Final.jar:7.1.1.Final]
        at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
        at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [classes.jar:1.6.0_30]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [classes.jar:1.6.0_30]
        at java.lang.Thread.run(Thread.java:680) [classes.jar:1.6.0_30]
Caused by: java.lang.NoClassDefFoundError: org/jboss/as/jpa/hibernate3/infinispan/InfinispanRegionFactory
        at java.lang.ClassLoader.defineClass1(Native Method) [classes.jar:1.6.0_30]
        at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631) [classes.jar:1.6.0_30]
        at java.lang.ClassLoader.defineClass(ClassLoader.java:615) [classes.jar:1.6.0_30]
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) [classes.jar:1.6.0_30]
        at org.jboss.modules.ModuleClassLoader.doDefineOrLoadClass(ModuleClassLoader.java:327) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:391) [jboss-modules.jar:1.1.1.GA]
        ... 23 more
Caused by: java.lang.ClassNotFoundException: org.jboss.as.jpa.hibernate3.infinispan.InfinispanRegionFactory from [Module "deployment.waimap.ear:main" from Service Module Loader]
        at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:468) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:456) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:423) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:423) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:398) [jboss-modules.jar:1.1.1.GA]
        at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:120) [jboss-modules.jar:1.1.1.GA]
        ... 29 more
 
At this point, I think it' reasonable for me to conclude that this is idiosyncratic to my particular environment/EAR. The same think happened on my Linux site For laughs, here's my persistence.xml:
 
<?xml version="1.0" encoding="UTF-8"?>
<!-- Persistence deployment descriptor for dev profile -->
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
  version="1.0">
  <persistence-unit name="waimap_pu" transaction-type="JTA">
                    <provider>org.hibernate.ejb.HibernatePersistence</provider>
                    <jta-data-source>java:jboss/datasources/waimap_ds</jta-data-source>
  <properties>
  <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
  <property name="hibernate.hbm2ddl.auto" value="validate" />
  <property name="hibernate.show_sql" value="true" />
  <property name="hibernate.format_sql" value="true" />
  <property name="jboss.entity.manager.factory.jndi.name"
  value="java:app/waimap_puEntityManagerFactory" />
  <property name="hibernate.default_schema" value="waimap" />
  <property name="hibernate.listeners.envers.autoRegister" value="false"/>
            <property name="jboss.as.jpa.providerModule" value="hibernate3-bundled" />
  </properties>
  </persistence-unit>
 
</persistence>
 
Here my jboss-deployment-structure.xml
<jboss-deployment-structure xmlns="urn:jboss:deployment-structure:1.0">
 
 
  <deployment>
  <dependencies>
  <module name="org.bouncycastle" slot="main" export="true"/>
  <module name="org.apache.log4j" export="true" />
  <module name="org.dom4j" export="true" />
  <module name="org.apache.commons.logging" export="true" />
  <module name="org.apache.commons.collections" export="true" />
  </dependencies>
  </deployment>
 
  <sub-deployment name="waimap.war-0.3.0.war">
  <exclusions>
  <module name="javax.faces.api" slot="main" />
  <module name="com.sun.jsf-impl" slot="main" />
  <module name="javax.faces.api" slot="1.2" />
  <module name="com.sun.jsf-impl" slot="1.2" />
  </exclusions>
  <dependencies>
  <module name="deployment.waimap.ear.waimap.ejb-0.3.0.jar"/>
  <module name="deployment.waimap.ear.jboss-seam-2.2.2.Final.jar" />
  <!-- 
                              <module name="javax.faces.api" slot="1.2" />
                              <module name="com.sun.jsf-impl" slot="1.2" />
                               -->
  </dependencies>
  </sub-deployment>
 
  <sub-deployment name="waimap-client.war-0.3.0.war">
  <exclusions>
  <module name="javax.faces.api" slot="main" />
  <module name="com.sun.jsf-impl" slot="main" />
  <module name="javax.faces.api" slot="1.2" />
  <module name="com.sun.jsf-impl" slot="1.2" />
  </exclusions>
  <dependencies>
  <!-- <module name="deployment.waimap.ear.waimap.war-0.3.0.war" /> -->
  <module name="deployment.waimap.ear.waimap.ejb-0.3.0.jar" />
  <module name="deployment.waimap.ear.jboss-seam-2.2.2.Final.jar" />
  <!-- 
                              <module name="javax.faces.api" slot="1.2" />
                              <module name="com.sun.jsf-impl" slot="1.2" />
                              -->
  </dependencies>
  </sub-deployment>
 
</jboss-deployment-structure>
 
The whole object of the game is to run a Seam 2.2.x App through jboss 7.1.1.Final. 7.1.0.FInal is working fine.